1. Technical Field
The present invention relates to a bonding method, a bonded structure, a liquid droplet discharging head, and a liquid droplet discharging apparatus.
2. Related Art
Conventionally, two base members are bonded (adhesively bonded) together by an adhesive such as an epoxy, urethane, or silicon adhesive.
For example, a liquid droplet discharging head (an inkjet recording head) incorporated in inkjet printers is constructed by bonding together components made of different materials such as resin, metal, or silicon with an adhesive,
In this case, a liquid or paste-adhesive is applied to a bonded surface of each component to bond the components to each other via the adhesive applied. Then, heat or light is applied to cure the adhesive, thereby achieving bonding between the components.
However, such an adhesive-based bonding has problems such as reductions in bonding strength and size precision, and a time-consuming bonding process because of its long curing time.
Additionally, in many cases, a primer is needed to increase bonding strength. Thus, cost and time for use of the primer leads to an increase in bonding cost and complication of the bonding process.
Meanwhile, as an alternative to the adhesive-based bonding method, there is a solid-to-solid bonding method.
In the method, without any intermediate layer such as an adhesive, components can be directly bonded to each other (See JP-A-1993-82404, for example).
The above bonding method, which uses no intermediate layer such as an adhesive, can provide a bonded structure with high size precision.
In the method, however, there are several problems as follows: (1) Materials of bonded members are restricted; (2) The bonding process requires heating at a high temperature (ranging approximately from 700 to 800° C., for example); and (3) Atmosphere during the bonding process is restricted to a reduced-pressure atmosphere.
Given the problems described above, there has been a demand for a method for bonding members to each other strongly with high size precision and efficiently at a low temperature regardless of the materials of the bonded members.